This month has already seen Yasiel Puig's dazzling debut with the Dodgers, Anthony Rendon's return to D.C., Gerrit Cole's promotion in Pittsburgh and Mike Zunino's assumption of Seattle's catching duties.

On Tuesday, two particularly prominent promotions will be added to the pile, adding a dose of drama to a couple of doubleheaders. Wil Myers will bring his right-handed power bat to the Rays' lineup in a twin bill in Boston, and Zack Wheeler will toe the rubber for the Mets in the nightcap of a day-nighter with the Braves at Turner Field, about 30 miles from his hometown of Dallas, Ga.

Each situation is, well, situation-specific. The Pirates had a legit need to add Cole to their banged-up rotation, and likewise the Bryce Harper-less Nats with Rendon. The Dodgers certainly don't seem to worry about tomorrow's payroll today.

But suffice it to say that any financial rationale behind stashing top prospects in Triple-A has been nullified by this point in the calendar. The Super Two arbitration cutoff is inherently a guessing game, yet general managers can feel fairly comfortable that a kid promoted today won't fall within the Super Two parameters at the end of 2015 and, ergo, won't be eligible for arbitration until after 2016.

That's why you typically have a rash of callups this time of year. It's not that Myers made some fundamental adjustments in his swing mechanics or that Wheeler suddenly found more zip in his fastball; it's just that their teams can now give them their big league break-in without worrying about what it's going to cost them three years from now.

At least the built-in business of arbitration-eligibility allows for these early-summer spurts of tantalizing transactions.

The thought of Myers, who entered the season ranked No. 4 on MLB.com's list of Top 100 Prospects, mashing in the middle of Tampa Bay's lineup is as tantalizing as it gets. But the Rays are quick -- and correct -- to temper expectations for the 22-year-old kid they obtained in the James Shields trade last December.

For one, Myers will be broken into the lower third of manager Joe Maddon's lineup. More to the point, Tampa Bay doesn't fundamentally need him to carry the load. The Rays, after all, are right in the thick of the American League East race because they've reinvented their offensive reputation, entering the week ranked fourth in the AL in runs per game (4.83).

"I think that's important," Tampa Bay executive vice president of baseball operations Andrew Friedman said. "I think the biggest thing is to just bring him up, let him fit in, be one of nine. The fact that we have been scoring runs is good."

Having said that, the Rays have several guys navigating their way through the corner outfield and designated hitter spots who have struggled against left-handed pitching: Kelly Johnson (.709 OPS), Ben Zobrist (.618) and Matt Joyce (.606). So Myers' right-handed bat at least has the potential to spice up Maddon's options on that front.

From the day Myers arrived at the club's Spring Training camp a couple of months after the high-profile trade, Tampa Bay embraced him with what Maddon calls the "liberal arts approach" to player development, de-emphasizing his offense and getting him to think more about the fundamentals of the game. But the Rays did want to see improvement in pitch selection from Myers after he got off to a slightly sluggish start to his season at Triple-A Durham, and he responded by belting seven homers in his last 18 days at that level.

Fans will want to see that kind of pop instantly at the highest level. It's only natural, even if it might not be entirely realistic. Yet you look at what Rendon has done in D.C. since his second big league callup, on June 5 -- a .444 average, with seven of his 16 hits going for extra bases -- and you can envision Myers having that kind of instant impact provided he doesn't let the pressure get the best of him.

We could use another potent power hitter in the picture, because frankly, we have no shortage of young pitchers tying big league batters in knots. If Wheeler comes as advertised -- as Cole no doubt has -- he'll fit right in.

Mets fans have looked forward to Wheeler's debut ever since his arrival to the organization in the Carlos Beltran deal at the Trade Deadline in 2011 -- a swap that could prove to be one of GM Sandy Alderson's finest moments. The sixth overall pick in the 2009 First-Year Player Draft, Wheeler, who entered the year ranked No. 7 on the Top 100 Prospects list, has racked up 73 strikeouts in 68 2/3 innings in the hitter-friendly Pacific Coast League. He went 4-2 with a 3.93 ERA in 13 starts -- numbers that aren't overwhelming, though the Mets openly wondered whether his focus was waning in Triple-A.

"There are guys that get bored," said manager Terry Collins, "who know they belong at the next level."

It remains to be seen if Wheeler's promotion is a long-term one or if the Mets will just use this as a spot start. But with a high-90s fastball and a hard curve, he has the raw stuff to stick, and the Mets presumably didn't make PR man Jay Horwitz fly 6,000 miles roundtrip to provide a face-to-face crash course on media training just for Wheeler to make a single start.

Probably best not to expect too much out of Wheeler and Myers on their first day. Still, Prospect Promotion Season has made it far from a typical Tuesday.